Three Chinese immigrants were found hidden in the trunk of a vehicle trying to cross into the U.S. from Mexico Tuesday.

The driver, Eun Ku Lee, a 33-year-old South Korean citizen, was trying to cross at the San Ysidro Port of Entry about 4:45 p.m. with a valid SENTRI pass when his illicit load was discovered, according to court records.

Lee, who was driving a Jeep Compass with Baja California license plates, told the U.S. Customs and Border Protection officer that he was alone and traveling to Chula Vista, the complaint states. He was stopped for a closer inspection because of undisclosed discrepancies.

In the cargo area under a stock cover, an officer found three women stuffed inside. They were from China trying to cross into the U.S. illegally, court records say.

One woman told investigators that she agreed to pay $60,000 to be smuggled to New York, while another said her uncle had paid her way across and she was going to pay an extra $2,000 if she made it to North Carolina. The third said her cousin had paid her way and she was going to New York.

The women are being held as material witnesses in the prosecution against Lee, who was arrested on a human-smuggling charge. Lee’s temporary visa allowing him to be in the U.S. legally was also revoked, border authorities said.

A San Diego federal magistrate judge set his bond at $20,000 during a hearing on Wednesday.

“Concealing persons in vehicles is dangerous and could have severe consequences,” Pete Flores, director of field operations for CBP in San Diego, said in a statement. “CBP is pleased that this outcome was not life threatening and the Chinese nationals were removed safely without medical complications.”

Authorities at San Diego’s ports of entry have seen an increase in Chinese being smuggled in hidden compartments. In fiscal 2017, which ended Sept. 30, CBP at California ports of entry discovered more than 261 unauthorized immigrants from China — nearly a 50 percent increase from the year before.

Investigators arrested Serafin Rangel-Martinez, a Mexican citizen who isn't legally present in the United States. (Photo courtesy of the Hidalgo County Sheriff's Office)

Smugglers kidnapped a Chinese immigrant last week in McAllen — and mercilessly beat the man when he refused to pay them $15,000, according to federal court records.

At 4:19 p.m. on Dec. 4, the McAllen Police Department responded to a strange call on the 200 block of South 48th Lane.

The caller said a Chinese immigrant "who appeared to be severely beaten jumped into their car pleading for assistance," according to the federal criminal complaint.

When police arrived, though, the Chinese immigrant had vanished. Witnesses said people traveling in a black SUV had kidnapped him.

Officers later found the man "along a roadside badly beaten," according to the criminal complaint. They transported him to the hospital.

At the request of U.S. Immigration and Customs Enforcement and the McAllen Police Department, CBS 4 News withheld details about the incident for several days to avoid interfering with the investigation.

The kidnappers apparently had second thoughts about dumping the Chinese immigrant and started making calls.

"McAllen Police Department Investigators responded and made contact with the concerned citizen who said that they were receiving calls from an unknown male claiming to be looking for the person who was requesting assistance," according to the criminal complaint.

Officers conducted a sting operation at the Fallas Paredes store on South 23rd Street, telling the caller they would hand over the Chinese immigrant.

When Serafin Rangel-Martinez arrived at the store looking for the Chinese immigrant, investigators arrested him.

Police contacted Homeland Security Investigations, a division of U.S. Immigration and Customs Enforcement, which sent federal agents to question Rangel and the Chinese immigrant.

The Chinese immigrant said smugglers demanded $15,000 after he illegally crossed the border, according to the criminal complaint. When he refused to pay, the smugglers beat him.

"He waited until the smugglers were busy and ran away to look for help," according to the criminal complaint.

The Chinese immigrant jumped in a car and convinced the occupants to call for help, according

to the criminal complaint. Smugglers dragged him away before police arrived.

The Chinese immigrant "claims once in the car the smugglers beat him with their fist and blunt objects until he was eventually pushed out of the smugglers vehicle, abandoned on the side of the road until discovered by a police officer, who took him to the hospital," according to the criminal complaint.

He suffered extensive injuries, including a puncture wound to the skull.

An attorney for the Chinese immigrant, who isn't legally present in the United States, didn't respond to a request for comment.

Rangel, a Mexican citizen who isn't legally present in the United States, remains in federal custody. He's charged with bringing in and harboring aliens.

An attorney who represents Rangel didn't respond to a request for comment.

The arrest of 30 Chinese and Mexican nationals who had entered the country without authorization led U.S. Border Patrol agents to uncover a clandestine tunnel spanning the U.S.-Mexico border near the Otay Mesa port of entry early Saturday morning.

A tunnel opening equipped with a ladder that was discovered near the U.S.-Mexico border on Aug. 26, 2017, is seen in a photo released by U.S. Customs and Border Protection.

The officials were patrolling the southern San Diego area, which borders the Mexican city of Tijuana, when around 1:15 a.m. they came across the group of migrants, who appeared to have just entered the country, according to a statement from U.S. Customs and Border Protection.

The agents searched the area and uncovered a crude hole in the ground that was outfitted with a ladder and concluded it was used to smuggle humans and illegal goods. The shaft would deposit people coming from Mexico just north of the secondary fence near the port of entry, officials said.

Agents plan to question the 30 migrants who were arrested about the discovery.

Among those taken into custody were 23 Chinese nationals — including 21 men and two women — as well as seven Mexican nationals, with four men and three women among them.

“While subterranean tunnels are not a new occurrence along the California-Mexico border, they are more commonly utilized by transnational criminal organizations to smuggle narcotics,” the CBP press release states. “However, as this case demonstrates, law enforcement has also identified instances where such tunnels were used to facilitate human smuggling.”

Officials with U.S. Immigration and Customs Enforcement responded to the scene and will be investigating the cross-border tunnel in conjunction with their Mexican counterparts.

This is certainly not the first surreptitious tunnel discovered along the U.S.-Mexico border nor the most sophisticated. In fact, officials said they believe it may be an extension of an incomplete tunnel that was previously identified and seized by Mexican authorities.

ICE hiring 10 thousand agents in sanctuary cities

BY JOSH DELK - 07/18/17 05:00 PM EDT

Immigration and Customs Enforcement (ICE) Acting Director Thomas Homan on Tuesday said he plans to further crack down on undocumented immigrants by sending more resources and agents to sanctuary cities.

"In the America I grew up in, cities didn't shield people who violated the law," Homan told the publication. “What I want to get is a clear understanding from everybody, from the congressmen to the politicians to law enforcement to those who enter the country illegally, that ICE is open for business."

"We’re going to enforce the laws on the books without apology, we’ll continue to prioritize what we do,” Homan continued. “But it’s not OK to violate the laws of this country anymore, you’re going to be held accountable.”

During his interview with the Examiner, Homan also praised the Trump administration, saying it has "taken the handcuffs off law enforcement," allowing them to address immigration more thoroughly.

"You can like President Trump, not like him, like his policies, not like his policies, but one thing no one can argue with is the effect they've had," said Homan.

According to Homan, illegal border crossings have decreased by 70 percent under Trump and arrests inside the country have increased by 40 percent.

The 30-year immigration agency veteran also said he has gotten a green light to hire 10,000 new immigration agents, who will work to arrest illegal criminals sheltered in sanctuary cities and elsewhere.

Sanctuary cities are jurisdictions with policies limiting cooperation between local law enforcement and federal immigration agents and include cities such as New York, San Francisco, Chicago and Austin.

President Trump campaigned on cracking down on illegal immigration and stepping up border security.